Ensure Authenticating as the Correct User

If you have multiple accounts, double-check that you are
authenticated as the right one!

In order to SSH into a CircleCI build, the username must be one which has
access to the project being built!

If you’re authenticating as the wrong user, you can probably resolve this
by offering a different SSH key with ssh -i. See the next section if
you need a hand figuring out which key is being offered.

Ensure the Correct Key is Offered to CircleCI

If you’ve verified that you can authenticate as the correct
user, but you’re still getting “Permission denied” from CircleCI, you
may be offering the wrong credentials to us. (This can happen for
several reasons, depending on your SSH configuration.)

Figure out which key is being offered to GitHub that authenticates you, by
running: